Transport and fleet managers will understand the frustrations around having a vehicle off the road for service. Downtime means the potential for decreased efficiency and surprise costs. Delphi Technologies has created a handy service guide for workshop technicians that helps to diagnose faults with Common Rail (CR) systems, ensuring any problems with a vehicle are found and fixed, swiftly.
Identify the fault code
The first stage in identifying Common Rail faults is to interrogate the vehicle’s OBD. By using a quality all makes diagnostic tool such as Delphi’s DS, technicians can identify the fault codes generated and then focus their attention on this area of the vehicle.
Check the injectors
If the OBD has generated a fuel injection system fault code, then check the injector’s functionality. Tools such as Delphi’s Sealed Rail Diagnostic Kit can be connected to the injectors, preventing the need for a complete system removal and refit. It collects and measures back leakage flow from the injectors and indicates which injector may be faulty and in need of replacement. By replacing individual injectors rather than a whole set, garages can save both time and money.
Check the Common Rail pump function
Next, fit the Sealed Rail Kit directly onto the high-pressure outlet pipe from the pump and crank the engine to record pressure in the system. The Sealed Rail Kit displays the results digitally and if the figure differs from the specified pressure measurement for the vehicle application, the pump could be faulty.
Confirm if a mechanical or electrical pump fault
If the Common Rail pump is suspected of being faulty, use Delphi’s False Actuator Kit in conjunction with the Sealed Rail for further interrogation. This temporarily replaces the vehicle’s actuator to enable the pump to generate full system pressure. If the pump generates the correct pressure with the False Actuator in place, then the vehicle actuator is likely to be at fault and should be replaced. However, if the pressure is still below the required level, then the Common Rail pump may have a mechanical fault and should be repaired or replaced. Both kits are compatible with Delphi, Bosch, Denso and Continental systems.
For more information call Tech ‘n’ Tools diagnostics Specialist Dave Molloy on 087 24 69 175 for more information.